Occupational accidents cause not only the deathor injury of workers but also the invisible loss of theowner/company. Occupational accidents also exertinfluence on business development and add to socialcost as well. Three kinds of causes of occupationalaccidents namely direct, indirect and basic cause;have been identified. Direct causes refer to energy,perilous objects or harmful objects which humanbeings come into contact. Indirect causes involveunsafe environments and unsafe behaviors. Basiccauses are concerned about the deficiency pertainingto safety management. According to statistics, of alloccupational accidents recorded, 98% fall on thecategory of “indirect causes.” That is, mostoccupational accidents are due to unsafeenvironments and behaviors/actions. No doubt,unsafe environments and unsafe behaviors are toblame for most occupational accidents. Therefore, ifwe can avoid unsafe environments and unsafebehaviors/actions, we can be free from occupationalaccidents. The present paper targets 14 causes as themain axis of analysis. After applying the interpretivestructure modeling (ISM) and the α-cut of the fuzzyclustering. Through strata analysis, the weightingbetween influencing factors is then obtained. Theresult is then subject to comparison with practicalconditions. Thus, future prevention policy ofoccupational accidents may refer to and benefit fromthis analysis.